Ice shelf insulation method

ABSTRACT

A method of slowing melting of the polar ice shelves is provided. The method comprises conveying air underneath the ice shelf, at least temporarily, forming an insulating layer between the ice of the ice shelf and the sea water below. The method may be carried out by drilling a hole through the ice shelf and conveying air through the hole until it reaches the water. The buoyancy of the air will position it between the sea water and ice, thereby insulating the ice from the melting sea water.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to slowing negative results of global warming. More particularly the present invention relates to a method of reducing ice shelf melt.

2. Description of Related Art

Ice shelves are extremely important to the environment because they essentially act as dams for ice streams and glacier melts originating from ice sheets and glaciers respectively. Both ice sheets and glaciers are located on dry land. When their ice melts, the water flows into the ocean because of their steep declinations, causing an increase in the global sea level. With warmer global temperatures due to global warming, this process is happening at a much faster pace than we have seen in the past. It is vital that ice shelves, which are essentially extensions of the ice sheets and glaciers that are already suspended in the water, remain intact, otherwise global sea levels will increase dramatically in the future.

While the ice shelves themselves don't directly impact sea level rise because they are already displacing nearly the same amount of water as if they were melted, they indirectly affect sea level rise by determining whether the melting ice on these ice sheets and glaciers have direct access to the ocean. Ice shelves can extend hundreds of miles into the sea from the “grounding line,” which is the point where the bedrock below the surface of the ice comes to an end and complete water suspension below the ice begins. As the ice shelf flows outward, it comes in contact with islands and bedrock beneath the water that produces a tremendous amount of friction. This friction produces a counterpressure on these ice sheets and glaciers, keeping their giant masses of ice from flowing into the water; thus, keeping them more stable. On Antarctica, both the West Antarctic Ice Sheet and East Antarctic Ice Sheet are located on opposite sides of the Transantarctic Mountains that extend almost 15,000 feet above sea level. This results in both ice sheets having very steep declinations. If it weren't for the ice shelves, the tremendous amount of pressure from both the ice and gravitational forces would cause these ice streams to flow much faster into the ocean.

In the last two decades there have been several ice shelves that have melted or broken up in the Antarctic Peninsula. Because of this, the speed of the ice flowing into the ocean has already been seen to increase dramatically on this peninsula, primarily since there are less obstacles to stop these ice streams from flowing into the water. The Antarctic Peninsula is now believed to be contributing to sea level rise from anywhere between one and three centimeters. It is therefore essential that these ice shelves remain intact, otherwise global sea level rise is going to impact humanity at a much quicker pace. The primary cause that is believed to be the main factor for the degradation of these ice shelves is the warming ocean undercurrents that are melting the ice from below. Scientists have found that changing wind patterns can help push these warm waters through deep ocean troughs and towards these ice shelves that extend towards glaciers and ice sheets. Because this warm ocean water rises, it can become trapped below these ice shelves, and begin the melting process from below the ice. The thinning of these ice shelves makes them extremely vulnerable to fracturing, the calving off of icebergs, and even eventual collapse.

Therefore, what is needed is a system and method that may help slow the melting of these ice caps.

SUMMARY OF THE INVENTION

The subject matter of this application may involve, in some cases, interrelated products, alternative solutions to a particular problem, and/or a plurality of different uses of a single system or article.

In one aspect, a method of slowing a melting of a polar ice shelf is provided. The method begins with selecting an area of an ice shelf that may benefit from a reduced rate of melting. Next, a hole is drilled through the ice shelf from a top surface to a bottom surface. A quantity of air or other gas is then conveyed through this hole. At least a part of this quantity of air is urged between the water and the ice forming a layer between the two, and thereby slowing the melting of the ice by the sea water.

In another aspect, a method of insulating a bottom surface of a polar ice shelf is provided. A hole is drilled through the ice shelf from a top surface of the ice shelf to a bottom surface. A quantity of air is then conveyed through the hole from the top surface of the ice shelf into the sea water underneath the ice shelf. This quantity of air, because of its buoyancy in the water, is urged between the sea water and the bottom of the ice shelf, thereby insulating the ice shelf from the sea water.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 provides a view of an embodiment of the method of ice shelf insulation in use.

FIG. 2 provides a view of an embodiment of the method of ice shelf insulation in use.

FIG. 3 provides a flow chart of an embodiment of the method of ice shelf insulation.

FIG. 4 provides a flow chart of an embodiment of the method of ice shelf insulation.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appended drawings is intended as a description of presently preferred embodiments of the invention and does not represent the only forms in which the present invention may be constructed and/or utilized. The description sets forth the functions and the sequence of steps for constructing and operating the invention in connection with the illustrated embodiments.

Generally, the present invention concerns a system and method for slowing a melt of polar ice shelves. The invention involves drilling through an ice shelf to pump air underneath the ice between the ice and water, and a corresponding method. The system includes a drill, an air compressor, and monitoring equipment.

A drill may be employed to penetrate the ice shelf to reach water underneath. This drill may be any device capable of creating a hole in the ice shelf. Examples of drills include, but are not limited to: conventional bit-drills, hot water melting devices, laser melting devices, and the like. In some embodiments, the drill may further comprise a sensor to indicate when the ice ends and water begins. The drilled hole may be any size capable of having air blown through it, and may vary in size depending on a quantity of air intended to be passed through.

Once the hole has been formed in the ice shelf from a top through to the bottom, a pressurized air source may be used to convey air or other gas through the hole, into the water, to be trapped between the ice and water interface. The pressurized air source may be any device capable of using pressure to direct a flow of air. The gas must be pressurized sufficiently to effectively flow through the hole and into the water under the ice, and to spread this air about the hole. Examples of pressurized air sources include, but are not limited to: compressors, pumps, and compressed gas cylinders.

While the term air is generally used throughout this disclosure, it should be understood that any gas may be used as an insulator between the ice and sea water. Examples of useful gasses other than air may include waste gasses, greenhouse gasses, gaseous hydrocarbons, and the like. Gas such as air is chosen because of its effectiveness as an insulator, it ready availability, and because of its ease of movement from a top of the ice shelf the bottom.

The outlet air from the compressor may be quite hot depending on the pressure, and it may be undesirable to pass heated air through the ice because it would cause the ice to melt. Therefore, a chiller may be in communication with an outlet of the compressor to chill the outlet air. The chiller preferably may decrease a temperature of the compressed air going into the ice hole to a temperature at least below 0 degrees Celsius. The chiller may be any mechanism capable of chilling the ice before it enters the hole in the ice. Examples of chillers may be a water bath, radiator, ambient chiller, fan radiator, and the like.

In an alternative embodiment, the ice at the edges of the drilled hole may serve to chill the air as it passes through. Heat from the compressed air may slowly expand the hole, allowing more air to pass through.

In one embodiment, air may be conveyed directly through the hole in the ice. In another embodiment, a pipe or other liner may be disposed through the hole. In still a further embodiment, the drill may further comprise a hole lining system that lines the walls of the hole with a pipe, tube, or the like, during the drilling process. In still another embodiment, a tube or pipe may extend to a bottom of the ice shelf. This tube or pipe may have a nozzle at its end, allowing adjustment and control of a direction of the air flow underneath the ice. The nozzle may be remotely movable, or angled, allowing control of direction of the air.

The flow rate of air through the hole may vary depending on embodiment. In one embodiment, the flow rate may be controlled based on monitoring, to ensure a steady flow as desired. Further in another embodiment, the flow rate may be controlled to match or overcome a rate of escape of the air from under the ice, causing a relatively steady state air layer underneath the ice.

In one embodiment, a cap may be used to seal the hole, preventing escape of gas or water from the hole.

The system may utilize a monitoring system to track progress and effectiveness of the air insulation. For example, radar, sonar, thermal monitoring, or the like, may be utilized to measure how far, and to what extent, the air layer has spread between the ice and the water. Movement of the air may also be tracked. The monitoring system may allow system users to know when to stop pumping the air through the hole, and also may allow them to know how much air to pump under the ice, when additional air must be pumped through. Further still, the monitoring system may allow users to track the effectiveness of the insulation method.

In one embodiment, after the hole is drilled, a monitoring device may be passed through the hole into the water below to map the underside of the ice shelf. This direct monitoring may be done by sonar, radar visual, or similar. The direct monitoring may allow system users to target weak areas, or identify areas that may store air effectively such as highly pitted surfaces, or concave areas. The pitted and concave surfaces may be particularly useful for capturing and storing the air for an extended period of time. These areas may then be targeted specifically by the insulation system.

In a particular embodiment, the hole may be drilled close to a grounding line of the ice shelf. The grounding line is a line at which the ice and land join. Beyond the grounding line, the ice is suspended over the top of the water. By drilling the hole close to the grounding line, air underneath the ice will have the longest passage to the surface, and thus likely the longest residence time under the ice for insulating purposes.

Turning now to FIG. 1 a view of an embodiment of the system in operation is provided. Land 10 can be seen supporting the ice 20. The ice 20 extends past the land over the sea water 30. The portion of ice 20 extending over the sea water 30 is the ice shelf. A hole 11 is formed by a drill 14 or similar hole creating device. The hole 11 extends from a top surface 15 to a bottom surface 16 of the ice shelf 20. An air compressor 13 or similar pressurized air source conveys air 12 through the hole 11. This air exits the hole 11 at the bottom 16, and is urged upward between the ice shelf 20 and the sea water by its buoyancy, creating a layer 18 between the water and ice. The air thus creates an insulation layer, slowing an ice melting rate caused by the warm sea water. Some of the air 17 will pass along the bottom surface of the ice 20 and past its edge, returning to the atmosphere. Also, some of the air 17 will be trapped by the pitted surface of the underside of the ice 20. Therefore, some of the insulating air will be fairly transitory, while some of it will be more permanent. The process may be monitored to determine if, when, and where additional air is required under the ice shelf.

FIG. 2 shows another embodiment of the system in operation. A detail view of the ice 20 is shown. A protrusion from the lower surface 21 of the ice 20 has trapped an air pocket 22, preventing the air from travelling along the upward-sloping ice 20 surface. This air pocket 22 slows heat transfer from the water to the ice 20 thereby slowing the melting rate of the ice 20. The air pocket 22 will remain substantially in place until it dissolves into the water, or is otherwise dislodged or released.

FIG. 3 provides a flow chart of an embodiment of the method contemplated herein. Initially, an area of ice shelf that may benefit insulation may be identified. This identification may be performed in any manner that may identify areas of the ice shelf that may be rapidly melting, weakened, or that may have features making this method of insulation particularly effective—such as a highly pitted lower surface that may catch a high percentage of air passed over it. Once identified, a hole may be drilled from a surface of the ice through to a bottom of the ice and into the water below. Air may then be pumped through the hole into the sea water. The buoyancy of the air causes it to rise and form a layer between the water and ice. As air continues to be pumped through, it will spread out in all directions. The process may be monitored, both during and after the air is conveyed into the water.

FIG. 4 provides another embodiment of the method contemplated herein. A hole is drilled from a surface of the ice shelf to a bottom of the ice shelf. Air is then pumped through the hole into the sea water. This air is, at least temporarily, trapped between the sea water and ice. After a period, the flow of air is stopped, and the hole is capped to prevent escape of the air. The air underneath the ice shelf may be monitored over time to track the positioning of the air layer. If the monitoring indicates a substantial loss of the air layer underneath the ice, the cap may be removed and air pumping may resume.

While several variations of the present invention have been illustrated by way of example in preferred or particular embodiments, it is apparent that further embodiments could be developed within the spirit and scope of the present invention, or the inventive concept thereof. However, it is to be expressly understood that such modifications and adaptations are within the spirit and scope of the present invention, and are inclusive, but not limited to the following appended claims as set forth. 

What is claimed is:
 1. A method of slowing a melting of a polar ice shelf comprising the steps of: selecting an area of an ice shelf that will benefit from a reduced melt rate; drilling a hole through the ice shelf from a top surface of the ice shelf to a bottom surface of the ice shelf in contact with sea water; conveying a quantity of air through the hole from the top surface of the ice shelf into sea water underneath the ice shelf, at least a part of the quantity of air forming a layer between the bottom surface of the ice shelf and the sea water, slowing the melting of the ice by the sea water.
 2. The method of slowing a melting of a polar ice shelf of claim 1 further comprising the step of monitoring the quantity of air under the ice shelf.
 3. The method of slowing a melting of a polar ice shelf of claim 2 wherein the step of monitoring the quantity of air under the ice shelf comprises measuring an area of the layer formed by the quantity of air between the sea water and ice using sonar.
 4. The method of slowing a melting of a polar ice shelf of claim 2 wherein the step of monitoring the quantity of air under the ice shelf comprises tracking a movement of the layer of the quantity air under the ice shelf over time using sonar.
 5. The method of slowing a melting of a polar ice shelf of claim 1 wherein the step of conveying the quantity of air comprises: activating an air compressor; and directing an outlet air from the air compressor into the hole in the ice shelf.
 6. The method of slowing a melting of a polar ice shelf of claim 5 further comprising the step of chilling air after it exits a compressor outlet.
 7. The method of slowing a melting of a polar ice shelf of claim 6 wherein the step of chilling the air comprises passing the air through a chiller device before the step of conveying the quantity of air through the hole.
 8. The method of slowing a melting of a polar ice shelf of claim 1 further comprising the step of capping the hole after the step of conveying the quantity of air.
 9. The method of slowing a melting of a polar ice shelf of claim 1 wherein the step of drilling the hole through the ice shelf is performed close to a grounding line of the ice shelf.
 10. The method of slowing a melting of a polar ice shelf of claim 1 further comprising the steps of: passing a probe through the hole; and mapping the bottom surface of the ice shelf using the probe.
 11. The method of slowing a melting of a polar ice shelf of claim 1 further comprising the step of directing the air conveyed at the bottom of the ice shelf.
 12. The method of slowing a melting of a polar ice shelf of claim 1 further comprising the step of passing a pipe through the hole.
 13. The method of slowing a melting of a polar ice shelf of claim 1 wherein the step of conveying the quantity of air is performed at a rate sufficient to overcome an escape of air from underneath the ice shelf.
 14. A method of insulating a bottom surface of a polar ice shelf comprising the steps of: drilling a hole through the ice shelf from a top surface of the ice shelf to a bottom surface of the ice shelf, the bottom surface being in contact with sea water; conveying a quantity of air through the hole from the top surface of the ice shelf into sea water underneath the ice shelf; wherein the quantity of air is urged between the sea water and the bottom of the ice shelf, insulating the ice shelf from the sea water.
 15. The method of insulating a bottom surface of a polar ice shelf of claim 14 further comprising the step of monitoring the quantity of air under the ice shelf.
 16. The method of insulating a bottom surface of a polar ice shelf of claim 15 wherein the step of monitoring the quantity of air under the ice shelf comprises measuring an area of the ice shelf insulated by the air from the sea water.
 17. The method of insulating a bottom surface of a polar ice shelf of claim 15 wherein the step of monitoring the quantity of air under the ice shelf comprises tracking a movement of the air under the ice shelf over time.
 18. The method of insulating a bottom surface of a polar ice shelf of claim 14 further comprising the step of passing a probe through the hole, and mapping the bottom surface of the ice shelf.
 19. The method of insulating a bottom surface of a polar ice shelf of claim 14 further comprising chilling air after it exits a compressor outlet by passing the air through a chiller device before the step of conveying the quantity of air through the hole.
 20. A system for use in insulating a bottom of a polar ice shelf comprising: a drill, the drill configured to form a hole through the polar ice shelf; an air compressor, the air compressor configured to compress ambient air and direct the compressed air through the hole and into a sea water beneath the ice shelf; a remotely movable nozzle positionable at a bottom of the hole, configured to direct the compressed air from the hole into the sea water; a monitoring device, the monitoring device configured to monitor a movement of a quantity of the compressed air that is beneath the ice shelf, between the ice shelf and the sea water. 